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arXiv · 1602.06743

Cosmological test with the QSO Hubble diagram

M. Lopez-Corredoira·F. Melia·E. Lusso·G. Risaliti
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Abstract

A Hubble diagram (HD) has recently been constructed in the redshift range 0 99% C.L. The Quasi-Steady State Model is excluded at >95% C.L. The remaining four models (Lambda-CDM/wCDM, the R_h=ct Universe, the Friedmann open universe and a Static universe with a linear Hubble law) all pass the test. However, only Lambda-CDM/wCDM and $R_{\rm h}=ct$ also pass the Alcock-Paczynski (AP) test. The optimized parameters in Lambda-CDM/wCDM are Omega_m=0.20^{+0.24}_{-0.20} and w_{de}=-1.2^{+1.6}_{-infinity} (the dark-energy equation-of-state). Combined with the AP test, these values become Omega_m=0.38^{+0.20}_{-0.19} and w_{de}=-0.28^{+0.52}_{-0.40}. But whereas this optimization of parameters in Lambda-CDM/wCDM creates some tension with their concordance values, the $R_{\rm h}=ct$ Universe has the advantage of fitting the QSO and AP data without any free parameters.

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M. Lopez-Corredoira, F. Melia, E. Lusso, G. Risaliti. 2016-02-22. Cosmological test with the QSO Hubble diagram. https://doi.org/10.1142/s0218271816500607

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